Restricted energy and materials resources, combined with the growing fears from various undesirable industrial byproducts, has increased incentives for developing new, cleaner and more efficient synthetic methodologies to aid the chemical industry in handling the global problems of pollution, growing energy demand and the shortage of raw materials. Metal organic frameworks (MOFs) are very attractive materials due to their large porosity, tunability in composition and topology, in addition to huge potentials of their use in fields such as catalysis, gas storage, gas sensing, greenhouse gases emissions control and many other separations. These promising hybrid porous solids are typically synthesized using solvo/hydrothermal routes. Other methods have also been proposed, including microwave-assisted solvothermal methods; microfluidics; ionic liquids; and electro-chemistry, which are all based on synthesis of MOFs in solutions.
However, these synthetic methodologies have proven to be of interest only for lab-scale research and have been minimally implemented at pilot or larger industrial scales. In addition to often being economically impracticable, the above-mentioned solution-based synthesis methodologies for MOFs suffer from the need to use toxic and/or corrosive metal salt reagents and generate acid byproducts. Recently, solvent-free methodologies use to prepare different MOFs, such as ZIF-8, MIL-100, and other analogues, were recently reported. However, these methodologies are not yet scalable, and are therefore limited to research applications. Pilot and industrial scale production of MOFs requires consideration of a number of aspects including scientific practicability, environmental friendliness, efficiency, and capital and manufacturing costs. These factors are not being suitably achieved by current MOF manufacturing methods. Accordingly, solvent-free and/or green synthesis methods which are scalable to an industrial level are greatly needed.